An unusual neck swelling
Dr Serge Maurice
FRCSE
Mauritius
Yes, life’s full of surprises!
Surprise No 1:
The Presentation
Hey doc,
do you
think my
neck’s a bit
swollen?
Presentation
• Fit, 50 year-old helicopter pilot. Felt something
‘give’ in his neck while doing his routine morning
100 ‘chin-ups’ two weeks previously and now
finds that his shirt collars are a bit tight
• PMH: Appendicectomy age 18, lithotripsy of
1.2cm bladder stone May 2002
• Dad had ‘something congenital removed from his
neck years ago’
Initial thoughts
• Looks like a branchial cyst, in which there
has been a small bleed due to the strain
while doing the routine 100 chin-ups!
• So, ask for a pre-op echo, just to confirm
Surprise No 2:
The echography
Echo Report:
• Large complex multi-loculated cystic mass,
4x8cms, closely related to the R thyroid
lobe. “Dense” liquid in one compartment,
more fluid in others. No solid component.
• Smaller complex cyst, 3x1.2cms, closely
related to lower pole Left thyroid lobe. Fluid
clear, but fronds of solid material seen in
anterior wall. Small cysts also seen within
the Left thyroid lobe
Second thoughts
• Large right branchial cyst and thyroid
disease on left side
• So let’s examine the patient again & ask
for some more tests
Second examination
• Deep neck palpation confirms a lumpy left
thyroid lobe
• TFT’s normal
• CATscan requested
CATscan report
• Well defined homogenous fluid filled cyst R side of neck.
Approx 10.6x5.4x4.8cms. Thin walled, extending from C4
to sternoclavicular joint, lying anterior to and abutting R
common carotid. R internal jugular vein lies just lateral &
is intimately related to it. It lies deep to R SCM muscle,
compressing and shifting to left the R thyroid lobe, the
larynx & the trachea. Posteromedially, mass extends to
tracheo-vertebral angle. After contrast, the wall remains
unchanged. The thyroid gland enhances vividly and is
well demarcated from the mass. Patchy enhancing soft
tissue noted within the mass.
• Isthmus normal. L thyroid lobe shows 2 small 1cm
diameter cystic lesions at its postero-lateral border
CATscan conclusion
• The mass on R side is more in keeping with a
branchial cyst than a thyroid cyst as the lateral
border of the thyroid is clearly demarcated from
the cyst. Furthermore, there is no enhancement
of the cyst wall with contrast. However the two
small cysts at the postero-lateral aspect of the
Left thyroid lobe are too small to characterize
and may represent thyroid cysts or small
branchial cysts
Surprise No 3:
The cyst
Operative notes
• R CERVICAL CYSTECTOMY & L
HEMITHYROIDECTOMY
• Wide horizontal collar incision. Large thin-walled
cyst full of haemosiderin stained serous fluid and
invading all tissue spaces under R SCM muscle.
? cystic hygroma. Easy finger dissection from
neck tissues and posterior aspect of R thyroid
lobe. Parathyroids identified & left untouched.
• L thyroid lobe knobbly with multiple cysts &
nodules. L thyroid lobectomy. Suction drain &
subcuticular fast Vycril to skin.
The left thyroid lobe
Surprise No 4:
The Histology Report
The report:
1. Cellular tumour showing predominantly
parathyroid chief cells with marked cystic
areas and evidence of recent
haemorrhages. Consistent with a
parathyroid adenoma with cyst formation.
2. The 2nd specimen is a multinodular
colloid goitre to which is attached a
parathyroid adenoma with identical
features to those in the 1st specimen
Low power view cyst R side
High power view cyst R side
High power view cyst L side
The Left thyroid lobe
Lab results( 2 weeks post-op)
• Normal thyroid function tests
• Serum Calcium level high limit of normal
(2.39mmol/L, - N: 2.2-2.55)
• Marginally high serum PTH (7.2pmol/L,
N:1.6-6.9) – This is now back to normal,
last test (26/09/06): 35 pg/ml (15-65)
Parathyroid cysts
• Rare. Until 1996, only some 200 cases
reported in the English literature. (Alvi et al
,1996)
• Typical parathyroid lesions measure <
3cm on sonography
• Cystic changes, giant size, multiloculated
configuration, inhomogeneous content and
calcification uncommon (Gooding, 1993)
•
Pathogenesis still unclear. Proposed
classification (Mallette, 1994):
1. Ontogenous – vestigial remnant of PTH
primordial cells of 3rd & 4th pouches
2. Coalescent – Due to coalescence of
areas of cystic degeneration in a normal
gland or an adenoma
3. Pseudo cyst – cystic degeneration of
an adenoma
• Most cysts are non-functioning, but if not,
the serum Ca and PTH levels reported to
be intimately associated with the size of
the adenoma (Castleman and Roth 1978)
• Hypocalcaemic crisis may follow removal
of a functional cyst, despite normal
remaining glands… (oops!)
Characteristics of PTH cysts
(Wang et al 1972)
• Usually loosely attached to thyroid with a
definite cleavage plane
• A cyst with a whitish, tough membrane
wall containing clear, watery fluid.
• A low lying position in the neck
Houston Case, 2002, extending in
mediastinum, tough calcified
capsule
Case reported in Brazil, 2006
Content of Brazilian cyst
In summary:
• A case of bilateral parathyroid cysts,
including a giant cyst, associated with a
multinodular goitre.
• Asymptomatic, but with a functioning cyst
(the smaller one)
• Utterly misdiagnosed!
LESSONS TO BE LEARNT:
Keep an open mind, listen to your
patient’s history carefully, discuss
investigative reports with your
colleagues if they do not match your
initial thoughts, but at the end of it
all, remember that medicine is an
inexact science!!
Merci.